This application has two goals. The first is to replace an outdated and unreliable electron microscope with a current, reliable model. The second goal is to extend the capabilities available to the Department of Anatomy and Neurobiology through the installation of a high performance electron microscope with special ancillary devices to which we currently do not have access. Together, this will give ongoing PHS supported biomedical research projects within the department: (1) enhanced quality of ultrastructural information, (2) increased efficiency for gaining this information, and (3) the ability to acquire new ultrastructural information not previously obtainable.